How does a pillow-top differ from a Euro-top or tight-top mattress?

A pillow-top has a distinct, visibly separate cushion on top of the mattress, often with a gap or seam between the top layer and the body of the bed. Euro-tops are sewn more flush with the mattress edges for a cleaner look, and tight-top mattresses have no extra top cushion at all, offering a flatter, more traditional surface.